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    <title>Document</title>
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    <script>
        //写一个函数计算n！
        //n 计算 1*2*3...
        //10!
        function jc(n){
            if(n==1)
                return 1;
            else
                return n*jc(n-1);
        }
        document.write(jc(5));
    </script>
</body>
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